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F. 'OBERHAENSLI INTERNAL uOMBUSTION' ENGINE AND IBTHOD 01" OPERATING,THE SAN! 3 Sheets-Sheet 1 g 1932. ori i al Filed Nov. 12. 1928 Re. 5 5

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INVENTOR A r101: NE VS I F. OBERHAENSLI I INTERNAL COHBUSTION'ENGINE ANDMETHOD OF OPERATING THE SAIB 3 Sheets-Sheet 2 3 1932. origi al r ledNov. 12. P928 Re. 18575 Tllc j- WITNESS I INViVTOR ,g fmzomcllOBERIl/INSL/ A TTORNE Y8 F. OBERHAENSLI INTERNAL COIBUSTI ON ENGINE ANDIEIHOD 0F OPERATING THE SA];

Aug. 23, 1932. r

3 Sheets-Sheet 3 Fi led Nov. 12. 1928 WITNESS IN 105 N TOR m ffilsamcbOBEAll/HVSLI A TTORNEYS Reiaued Aug. 23, 1932 j Re. 18,575

HD3101! 03811, O]? BREGENZ-LO CHAU, AUSTRIA, ASSIGNOB '10 fOIOU AITIENG1 LAND nrrmu. conus'rxox menu: m maon-orornna'rme sun;

1 V s ,1 oonromnoN- or swrrznn- Original Io. Luann, dated Kay 1:, mo,Serial resume, as number 1:, ms, and in Germany December 1, 1987.Applieaflonjor reissue filed February 80, 1882: Serial No. 584,844.

My invention relates to internal combustion en ines and moreparticularly to engines adapte to employ a heavy and diflicultlyvolatilizable fuel which is sprayed under I pressure during thecompression stroke into a com ression space in constricted connectiowith t ecylinder of the engine.

It is an object of the present invention to provide an engine of theabove indicated 10 character which is so constructed and operated thatsubstantially complete vaporization of the oil and practically perfectmixing of the oil vapors with the air for supporting combustion areobtained, whereby complete 1 combustion and consequently highefliciencyresult.

Internal combustion engines which employ heavy oils as fuel as nowconstructed may be classified either as ignition head motors or asantechamber Diesel .engines. In ignition head motors, in order toprovide the time necessary for vaporization and mixing, the fuel isinjected upon the ignition or incandescent head during the suctionstroke. High compression cannot be employed in such en- 'nes aspremature ignition must be avoided.

11 certain types of ignition head machines In which the fuel is injectedshortly before the endof the compression stroke, the compressionpressure can be increased without danger of premature ignition. Suchincrease of compression is, however, limited because of the reducedstrength of the ignition head re sulting from its highv heating.

In antechamber Diesel engines in which the fuel is charged into a cooledantecha-mber at the end of the compression stroke, the compression mavbe made of as high a degree as Ydesired. The antechamber of such enginesis. however, so small that only a small part of the fuel in such chambercan find the quantity of air necessary for combustion while the mainportion of the fuel is burnt in the compression space of the cylinder..A partial explosion first takes place in the antechamher and theunburnt fuel is forced into the compression space of the cylinder abovethe piston, where it burns. En 'nes'of thist e W require very highpressures in order to e ect 2116 lself-ignition of the diflicultlyvaporizable The im roveel internal combustion engine forming t e subjectmatter of the present in- I vention lies, with regard. to thepro-ignition pressure used, between the ignition head and theantechamber Diesel engines. With a compression ratio of 1:8 to 1:10,'the explosion pressures lie between 15 and 25 atmospheres. The highpressures common in Diesel engines are unnecessa as the ignition of thefuel is accomplished y means of an incandescent element. As a result ofthe lower pressures pureferably employed by me, the mixing of el and airis somewhat retarded, but I over- 1 come this difliculty by constructingthe en'- gins in such manner that the air for comustion is divided b theincandescent body into two currents ha ing great whirling energy orturbulence. The incandescent bod is constructed preferably in the formof a ll suspended in the combustion chamber, and in s aoed relationthereto. This bell divides t e air into two streams, one of which flowsdirectly. into the bell while the other flows along t the air streamsflow over a liar e heated surface and are uiekliiieated, while thereduced space into w ich t streams flow causes-inereased velocity andturbulence, particularly e whole fuel charge is injected into atleastone of these air streams just before the end of the compressionstroke while the streams are still in motion, so that the turbulence ofthe air causes a thorough intermingling of;the fuel therewith. Thecombustion chamber referably communicates with the lfylindier tlfrough arestricted opening or nec In the preferred form of the invention, thefuel charge is injected into the bell. The inlet openin for the fuelisso arranged with respect to e neck portion that only a part of the airis forced with the fuel stream directly into the interior of theincandescent body, the remaining air which ultimately enters theinterior of the incandescent body being first deflected about at least aportion of t e exteri or surface of this body. That portion of I e outersurface thereof. In this way,

lll lhflt before the end of the compression stroke.

.the air which enters directly, is insuflicient to support completecombustion of the fuel within the glowing element and forms with suchfuela pro-mixture of gas and air, which mixture is rendered completelycombustible or rapidly ignitable only upon addition of air which hasflowed around the incandescent body. y r

In the accompanying drawings which illustrate by way of example threetypes of engine having my invention embodied therein, Figs. 1 and 3 arepartial longitudinal sections through four-stroke engines; Fig. 2 is apartial longitudinal section through a twostroke engine, and Fig. 4 is asection along the line 4-4 of Fig. 3.

Fi 1 shows a water cooled cylinder 1 provide with a similarly cooledcylinder head- 2 in which are located two valves (3) for controlling theinlet of air and the exhaust of the engine, and in which is provided acombustion space 6 preferably of'spherical outline. A piston 4 which isconnected in well known manner to a crank shaft (not shown) fills thespace 5 almost completely at its upper dead center position. As aresult, the compression forces substantially all of the air into thecombustion space 6. This space is preferably separated from the maincylinder space 5 b a neck or constricted passageway 7. A bell shapedincandescent body 8, provided with an opening 11, is located wlthin'thespace 6 and operates both as a vaporizer'or heater for the heavy-oil, asa heater for the air,'and as an igniter for the fuel-air mixture. Thisincandescent body is suspended from one of the walls of the cylinderhead, in amanner to provide intermediatespaces 9 and 10, and preferablyso as to cover partially the neck or opening 7 and thus act as adeflector for the incoming air. The whole fuelcharge is sprayed'throu'ghthe opening 11 into one ofthe air streams, for instance, the one whichflows into the interior of the incandescent body 8 by means of a fuelnozzle 12. The body 8 is so disposedwith relation to the neck 7 and tothe fu'el stream discharged by the nozzle 12that the stream of air intowhich the fuel was injected can reach the surface of such body only bypenetrating the stream-of fuel. For exam le, the body may overlie aportion of the neck 0 ning and thus check the direct entry of air om thecylinder into the interior of the body 8, thus forcing this air streamto pass through the fuel stream before reaching the interior of saidbody. The body 8 thus divides the incoming air into two streams orportions. Both of these streamsspreadover the'surfaces of the bell 8while in a state of turbu-' lence and are quickly heated thereby. Fuelis injected into at least one of the streams and through the turbulenceof this stream is intimately mixed with hot air.

In the preferred form, one portion ofthe of the engine.

air flows through the open neck section between the edge of the opening11 of the incandescent body and the cylinder wall, strikes the fuelstream, penetratesthe same and is projected therewith into the interiorof such incandescent body, substantially without having traversed thesurface of the outer wall of the incandescent body 8. This portion ofthe air forms with the fuel a re-mixture of gas and air which, however,ecause of the low proportion of air, is not completely ignited under theconditions prevailing withln the combustion space. The second portion ofthe air strikes the outer surface of and is deflected by theincandescent body, flows into the intermediate space 9 and thus aroundat least a portion of the outer surface of the incandescent body, andmeets the whirling pre-mixture in the space in front of the opening 11,such pre-mixture then mixing with such second stream or portion of theair to form a complete, i. e. ra idly inflammable, mixture. It is to be0 erved that the first portion of the air above referred to whirlin intothe 'enlarged mixing space 10 filled w th the pre-mixture after beingheated by intimate contact with the outer surface of the incandescentbody. It is to be observed, however, that while the space 9 is narrow incross-section, it presents a relatively large cross-sectional area ofadmission to the incoming air due to the fact that it is coextensivewiththe exposed outer surface of the incandescentbody. This second stream orportion of air, which has been heated and somewhat delayed in itsdeflected course about at least a portion of the outer surface of theglowing element, serves to form a rap-' I idly inflammablelnixture withthe pre-mixture of the first mentioned stream of airand the fuel.

The incandescent body 8 is loosely supported from the side of thecylinder head by means'of a flange 13' and is so held by a cover flange1 4 that it can expand freely as it becomes heated. Upon removal of theflange 13 the'body 8 can be easily removed.

The flange 13 has an opening 15 which is adapted to receive anincandescent spiral 16 or similar priming apparatus, which may be heatedto incandescence by any suitable means,-for igniting the mixture uponstarting This apparatus is shown as carried by the cover flange. As soonas the engine becomes warm the mixture of fuel and air is ignited by theincandescent body 8 and the auxiliary igniting apparatus may then be outout.

In the two-stroke engine illustrated in Fig.

2, the inlet and outlet openingslS for the air flat top piston, insteadof the round top iston' illustrated in Figs 1 and 2. Fig. 4, w ile across-section only of Fig. 3, serves to illusgo trate the constructionof Fig.1 and 2 of which therefore no cross-sectional views are shown.

The method of forming the explosive mix- 'ture in accordance with myinvention makes it possible to utilize, even at compression rationsunder 1:10, heavy oils such as have otherwise been capable of use onlyin Diesel engines, and to produce intimate admixture thereof with air.The explosion pressures in my improved engine may be far below themaxlmum pressures of- Diesel engines and ma approximate the pressurescommon 'in or inary gas engines. The consumption of fuel is notappreciably higher than that of Diesel engines. As the gas-fuel mixtureproduced by my invention 1s an intimate one, my improved engine mayoperate at the high speeds which are common'in ordinary gas engines. Myen- 40 gme can therefore be run as a high speed motor and is thusadapted for the driving of automobilesand aeroplanes. Very higheflimoney is obtained with my im roved engine because the combustion iscomp etc and no unburnt fuel is carried oif by the exhaust. A

further im ortant feature of my invention is that the ho y 8, which actsboth as a vaporizer and an igniter, remains completely clean and doesnot become coated with a layer of carhon. Because of the fact that the.fuel is not directed upon thepiston and into the cylinder, the latterdonot become covered with un-,

burnt residual matters I The spherical form of the combustion space 6and of the incandescent body has a favorable and important influenceupon the production of whirling wlthin the air streams and thus upon thecompletion of the'mixture' of air and.

fuel. It will be obvious, however, that the incandescent body.8 .mayassume other forms than the spherical and it is 'to'be understood thatwhere in the claims I employ the term bell-shaped body the same is to becon; strued generically as including all suitable 55 forms 0 hollowbodies having an opening to cause of this conreceive a stream of air andcapable of being so positioned within the combustion s ace that anintermediate space is rovide betilwegn such body and the walls o thecylinder I It is not necessary to the practice of the invention that thestreams should form a premixture in the bell to which is added the airflowing around the bell. Good results can be obtained in any arrangementin which the air is divided into two streams which flow one into and theother around the bell, with injection of fuel into at least one'of thesestreams during the compression stroke.

My invention may be employed with equal advanta e in vertical and inhorizontal en- I ines. ther -variations from the specific orms shown anddescribed may be resorted to within the scope of the appended claimswithout departing from the spirit of my invention.

I claim: I s 1. A heavy oil motor comprising a cylinder, a pistonslidable therein, an air inlet valve, a hollow member associated withsaid cylinder and definin a compression space into which a charge 0 airis adapted to be forced and compressed during the compression stroke ofthe piston, said space communicating with the interior of said cylinderthrough a constricted passageway, a bell-shaped body pro- I vided withan opening and positioned within said member at least partially inspaced relation thereto, whereby an intermediate space between said bodyand said member is formed, and a fuel nozzle arranged to spray a streamof fuelinto the interior'ofv said body through the opening thereof, saidbody'being adapted to become incandescent during the operation of themotor to vaporize and ignite said fuel,

and being so disposed with respect to said passageway as to divide thecurrent of air mto two streams'such that part of the current of airenters directly with said fuel into said body and part is' deflectedinto the intermedi-.

ate space about said body, whereby a pro-mixture of air and fuelcomprising'a mixture slow to ignite is first formed in said body, saidpremixture .becoming rapidly inflammable) on mixing with the airstreaming around said body through said intermediate space.

I 2; A heavy oilmotor as set forth in claim 1, wherein said bell-shapedbody is so positioned as partially to cover said passageway, whereby theportion of the air entering with the fuel into the interior of said bodyattains a high velocity and is set into violentwhirling. g v

3. A heavy oil motor as set forth in claim 1, wherein said fuel nozzleand said bellshaped body are so disposed with respect to each other thatthe portion of theair'flowing through said passageway and into said bodymust penetrate the stream of fuel digected by said nozzle into theopening of said 5. A heavy oil motor as set forth in claimv 1,wherein'the interior walls of said hollow member and said incandescentbody are substantially spherical in form.

6. A heavy oil motor as set forth in claim 1, wherein said fuel nozzleis so disposed I with relation 'to said passageway as to dipassageway,whereby said first part ofthe rect the stream of fuel at an angle to thedirection of flow of the air through said 'air impinges upon andpenetrates said fuel;

stream prior to its entry into said body."

7. A heavy oil motor comprising a cylinder, a piston slidable therein,an air inlet valve, a hollow member associated with said cylinder anddefining a compression space into which a charge of air is adapted to beforced and compressed during the compression stroke of the piston, saidspace communicating with the interior of said cylin- V der through aconstricted passageway, a fuel divide the air nozzle arranged to spray astream of fuel into said space, and a deflector partially obstructingsaid as'sageway and arranged to owing through said passageway into twostreams, one of saidstreams being directed toward'the fuel stream at asubstantial angle thereto to form a pre-mixture therewith, saiddeflector being positioned to initially deflect the second air streamaway from said fuel stream during the formation of the re-mixture andbein of such shape as ultimately to direct'suc second air stream intosaid pro-mixture, whereby a final combustible mixture is formed. I

8. The method of operating an internal combustion engine having anincandescent ignition element within its combustion space and to whichseparate charges of air and fuel are fed, which comprises first mixingsaid fuel within said combustion space during the compression strokewith a portion of the air charge to form a pro-mixture therewith, andthenheatingthe remaining air while guiding it in a flowing stream andconducting to such mixture such flowing streams of the remaining air tof rm the final explosive charge, toward the e ofthe compression stroke.

9. The 'method' of operating an internal combustion engine having anincandescent ignition element within its combustion spare,

which comprises spraying a charge of fuel into such space during thecompression stroke of the iston while simultaneously compressing a carge of air toward said space, dividing such air into two portions, oneof said portions-being directed toward said space to mix with said fuelto form a pre-mixture therewith, and heating and directing the remainingair by a separate path in a flowing a rapidthe resulting stream of airin such manner. that a portion thereof impinges against said fuel streamat a substantial angle thereto, whereby said portion of the air .iscarried along with said fuel and forms a pre-mixture with the fuelvapors, and heating and imparting a whirling'motion-to the r f'der ofthe charge of air and directing t 6 same by a difl'erent path towardsaid pre-mixture to form a final rapidly inflammable 'mixture therewith.1

11. The method of operating an internal combustion engine having ahollow incandes-.

cent ignition element within its combustion space and to which separatecharges 'of air and fuel are fed, which comprises feeding air into saidcombustion space and dividing saidair into two streams one of whichflows to the inside of said incandescent element while the other flowsaround the outside thereof, and injecting fuel at a point outside saidignition element into ,one of said streams near butbefore the end of thecompression stroke, whereby said fuel enters said stream while it isstill in motion and is mixed therewith by the turbulence thereof, saidand any fuel mixed therewith being suppl ed with 'heat and the fuel-airmixture being ignited by said incandescent element.

12. The method of operatin an internal combustion engine having a ho owincandescent ignition element within its combustion space and to whichseparate charges of air and fuel are fed, which comprises feeding airinto the cylinder of the engine, compressing said air by the piston intosaid combustion space and dividing said-air flowing into said combustionspace into two streams one of which flowsto the inside of saidincandescent element while the other flows around the outside thereof,and injecting fuel into one of said streams at a substantialanglethereto near but before the end of the compression stroke whereby saidfuel enterssaid stream I while 1t is still in motion and is mixed there-I with by the turbulence thereof, said streams and any fuel mixedtherewith being supplied with heat and the fuel-air mixture beingignited b 7 said incandescent element.

13. he method of operating'an internal combustion engine having anincandescent element of large surface area within its combustion s aceand to which separate char of air an fuel are fed, which comprisesdividing the air charged into said combustion s ace into a plurality ofturbulent streams w ich combustion engine to w contact with the surfacesof the incandescent element and receive heat therefrom, and infuel intoone of said streams at a oint outside said ignition element near butfore the end of the compression stroke while said stream is still in astate of turbufuel when the air of both streams contams at inder,

valve, a ollow member associated with said' least a part of said fuel.

.15. A heavy oil motor comprising a cyla iston slidable therein, an airinlet cylinder and defining a compression space into which a charge ofair is adapted to be forced and compressed durin the compression strokeof the piston, a be -shaped body pfovided with an opening and positionedwithin said member at least partially in s aced relationthereto, wherebyaninterme- 'ate ace between said bod and said member is ormed andwhereby e air current is divided into two streamsone of which flows intothe interior of said body through the opening thereof while the otherflows into the ace around said body, "means located outinder, a valve aforced and compressedd side of said body operated near but before theend of the compression stroke to spray a stream offuel into one of saidair streams, said body becoming incandescent during the operation of themotor to ignite the formed fuel-air mixture, both said air streams-andany fuel mixed therewith being supplied with heat by said body, saidreceiving said fuel while in motion and by turbulence, causing anintimate mixture between the fuel and air.

16. A heavy oil motor comprising a .cyl-

iston slidable therein, an air inlet ollow member-associated with saidcylinderand defining a compression space intowhicha charge of ,air isadapted tobe shape 'POSltiOIlt-ld. within said member at least paruringthe. compres-f sion the piston, said space communicating with theinterior of said cylinder through a constricted passageway, a 'bellbodyprovided with an opening M i;

tially in spaced relation thereto, whereby an intermediate space betweensaid body and said member is formed and whereby the air current 1sdivlded into two streams oneof which flows into the interior of saidbody through the opening thereof while the other flows into the spacearound said body, means operated near but before the end of thecompression stroke to spray a stream of fuel into one of said airstreams at a substantial angle thereto, said body becoming incandescentduring the operation of the motor to ignite the formed fuel-air mixture,both said air streams and any fuel mixed therewith being supplied withheat by said body, said air stream receiving said fuel while in motionand by turbulence causing an intimate mixture between the fuel and air.

17 A hea oil motor as set forth in claim 16, wherein t member and saidincandescent body are substantially spherical in form. 5

18. A heavy oil motor comprising a cylinder, a iston slidable therein,an air inlet valve, a ollow member associated with said cylinder anddefining a compression space into which a charge of air is adapted to beforced and compressed during the compression stroke of the piston, saidspace communicating with the interior of said cylinder through apassageway, a bell-shaped body provided with a single opening only andpositioned within said-member at least partiallyin' spaced relationthereto, whereby an intermediate space between said body and said memberis formed, said body being so dieposed with respect to said passagewayas to ivide the air current into two streams such that one of thestreams flows into the interior of said body through the opening thereofwhile the other stream flows through the space around, said body andthen through said openin into said body, means operated near but be orethe end of the compression stroke to spray a stream of fuel into one ofsaid air streams, said body becoming incandescent during the o ration ofthe motor to i its the formed el-air mixture, both sai air streams andany fuel mixed therewith being supplied with heat by said body, said airstream receiving said fuel while in motion and by turbulence causinganintimate mixture between the fuel andair.

- 19.-'A heavy oil motor comprising a cyl-' inder, a piston slidabletherein, an air inlet valve, a hollow member asoeiated with saidcylinder and defining a compression space into which a charge of air isadapted to be forced and compressed during-the com ression stroke of thepiston, a bell-shaped y e interior walls of said hollow W provided witha single ning only and positioned within said mem er at least partlally.in s aced relation thereto, whereby an interme late space between saidbody and said member-is formed and whereby-the air current is dividedinto two streams one of which flows into the interior of said bodythrough the opening thereof while the other flows into the space aroundsaid body, means operated near but before the end of the compressionstroke to spray a stream of fuel into one of said air streams, said bodybecoming incan descent during the operation of the motor to ignite theformed fuel-air mixture, both said I air. streams and any fuel mixedtherewith being supplied with heat by said body, said air streamreceiving said fuel while in motion and by turbulence causing anintimate mixture between-the fuel and air. In testimony whereof I havehereunto set mysignature. v r r a FRIEDRICH OBEBHAENSLI.

